Non-offset surface-covering for impression-cylinders.



J. F. HASKINS.

NoN-pFFSET SURFACE covERpNG FOR IMPRESSION cYLlNDERS. APPLICATION FILED APR.23, 19,5. 1,148,381.

Paten-ted July 27, 1915.

IN1/furbi? J F Haskins.

I By

mtv/mfr seed oil. and lampblack. in the proportions b v weight ot' substantially ten parts india rubber. ten partel turpentine. twenty parts bemin. forty-tive pa rts linseeil oil. five parts .lamp-black. This rubber varnish is preterably made by dissolving and mixing b v agitation and `friction the india rubber. turpentine and benzin. and to such completed mixture are added the linseed oil and lampblack. stirring very thoroughly. A. second or japan coating is then applied. said coating being composed of copal gum. alcohol. glycerin. and rubber varnish made as described above. The relative proportions of these parts tor making the japan coating are substantially by Weight as tollovvs: ropal gum. twenty parts: alcohol. one hundred parts; glycerin. one part. and rubber varnislnone part.

Among the primary virtues of this surface coating 1:2 is that it has proved in practice to be absolutely non-otlset or inkand oil resisting. whereby there is no deposit made upon it from the printed sheet While receiving the second impression. Thereby l am able to produce a perfectly clear and satisfactory printing etlect. Without the use ol. a tympan sheet ot' muslin or other fabric which is so cmnmonly used. ln fact. my printing result is clearer and better than when the tympan sheet is used.

'Vlie surface coating l2 above referred to ot' a pronounced wear-sustaining nature., it having` proved capableo" sustaining from three to live million impressions Without change and without requiring to be renewed. rl`he actual vvear found not to exceed more than tvvo one-thousandths ot an inch as indicated by micrometer caliper to each million impressions. thereby making it possible to maintain nearly perfect unit peripheral relation ot' plate and impression cylinders and to hold to nearly true pitch line the relation of the gears.

As is yvell recognized in the operation ot large cylinder presse, much ditliculty Vis encountered as a result ot' static electricity in cold snappy Weather. thus the tension which must be maintained under ordinary circunu aces upon the paper to hold a smooth pulling web and a proper head margin'cut-otl'i.-i unnecessarily great, resulting frequently in. the parting of the paper it the pull thereon sutlcient to prevent the wrinkling of the paper andl bail margin cutoli"A due to the electrical intluences ci'unmon to the vusual blanket constructions. ru at yirdance with this invention however. due

nasser tricity. and hence the machine and paperv may be operated uniformly smoothly at all times.

l am avv-are that numerous propositions have been made as improvements in printing press blankets. some ot' which claim to be ot' an oiland ink-proof nature. but, in my vast experience as a printing press experta l believe I am the first to devise a printing press blanket or a surface coating for a printing press blanket orpacking which has the property. not only of being a non-absorbent ot ink and oil. but one which actually resists the reception ot' the surplus ink, oil or smut from the printed sheet passing over the impression cylinder' coated with my improvement.

l claim:

l. The herein described non-otlset surface covering for printing press blankets, the same comprising a composition ot matter including a chemically neutralized composition of gelatin. kept in sott condition by they addition ot glycerin. and rubber, with overlying japan made trom an alcohol sol-K -f vent, copal gum and another vegetable gum and a small percentage ot' glycerin.

The herein described coating for a printing press blanket. the same comprising a mixture of chemically neutralized gelatin, glycerin and rubber. and an overlying surtace coating comprising vegetable gums in solution and including a small portion of glycerin.

3. The herein described coating material for printing ,press blankets, the same cornprising a main body coating including a mixture of glycerin and rubber, and a surface coating therefor of ink-resisting Wear sustaining properties incli'iding an alcohol solvent, copal gum.

4. In a surface covering for printing press blankets. the combination of a chemically neutralized composition of gelatin, an oil, and rubber. constituting a plastic body adapted to impregnate the blanket to which it applied. and a surface coating therefor of an iuk-resisting Wear-sustaining 4nature comprising a solution ofvegetable gums. and v a small percentage ol glycerin. JOHN F. HASKNS. lfVitnes-ses:

that ll. Bruna. Plural l). lloLriraLs. 

